1. Field of the Invention
The present invention relates to an ophthalmic laser treatment apparatus which is used to treat a patient's eye by irradiating the eye with a laser beam.
2. Description of Related Art
Photocoagulation or the like of the tissue of fundus is generally performed as ophthalmic laser treatment. As a recent treatment method for age-related macular degeneration (AMD), attention is being given to Photodynamic Therapy (PDT) and Transpupillary Thermotherapy (TTT).
The PDT is a treatment method to treat choroidal neovascularization by intravenously injecting a photosensitive material (a pharmaceutical drug) having the property of selectively accumulating in atypical tissue such as choroidal neovascularization into a patient's arm, and irradiating an affected part of the fundus with a laser beam with a specific absorption wavelength to the drug, so that the affected part is cured by the active oxygen having cytotoxicity produced by the action of the drug. In the photocoagulation, thermal action spreads from a local point of a focus to an ambient region thereof. This would pose a limit to the treatment for choroidal neovascularization in central fovea or a contiguous region thereto. However, the PDT allows the treatment for choroidal neovascularization without causing damage to visual cells even in the central fovea.
On the other hand, the TTT is a noninvasive thermotherapy utilizing slow-acting atrophy or hypofunction of tissue cells by the heat induced by a laser beam from a laser diode or the like. The histologic fragile structure such as the choroidal neovascularization is of high sensitivity. Applying only a small temperature rise to the structure can necrotize the tissue thereof.
To perform the above photocoagulation, PDT, and TTT, heretofore, a hospital's ophthalmology division or the like needs to have some apparatuses (special purpose apparatuses) each having a delivery unit specifically designed for each type of treatment.
However, preparation of the special purpose apparatuses adapted for respective treatments would cause a problem that a wide space is needed for installation of those apparatuses. In addition, the preparation of the specially designed apparatuses would place a burden in cost on the ophthalmology division or the like.